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FRINGE CHARACTER
Until 2001 feathered dinosaurs were known only on the saurischian
branch of the dinosaur tree, which includes birds. That year a fossil
from the other branch, the ornithischians, surfaced on the international
market, with long, curved filaments on its tail. Without more informa-
tion on Psittacosaurus, scientists were reluctant to believe dinosaurs
so distantly related to birds bore featherlike structures. The 2009 an-
nouncement of similar filaments on another ornithischian, Tianyulong,
changed many minds. But did the trait evolve independently in the
two branches, or in their common ancestor?
PSITTACOSAURUS SP., 125 TO 121 MYA, CHINA; SMUGGLED SPECIMEN OF UNKNOWN PROVENANCE, CURRENTLY
IN CUSTODY OF SENCKENBERG RESEARCH INSTITUTE, GERMANY, PENDING REPATRIATION TO CHINA